I have a Naim Nait 5i amp with a Naim CD 5 CD player and KEF Q300 speakers. I also have a Sonos system to play music stored on my computer through my hifi system. About 60% of the music I play is from computer / Sonos and about 40% is via CD. Would a DAC improve the system my budget would run to a Rega or Arcam. Also, I had thought about the Arcam Sonlink but this would only help when music played from the Computer